Superatmospheric pressured steam setting of dye on web in a tube

ABSTRACT

A METHOD OF SETTING DYE ON A DYED WEB OF FABRIC COMPRISING PASSING THE WEB UNDER TENSION THROUGH AN ATMOSPHERE OF LIVE STEAM AT SUPERATMOSPHERIC PRESSURE UNTIL SAID DYE IS SET.

J. SERBIN Oct. 26, 1971 SUPERATMOSPHERIC PRESSURED STEAM SETTING OF DYE ON WEB IN A TUBE 8 Sheets--Sheet 1 Original Filed June 19, 1964 u r m 1 M m Wm Q? l M/VENTOR JA (:00 SE/PB/A/ er mill ATTORNEYS.

Oct. 26, 1971 J SERBlN 3,614,198

SUPERATMOSPHERIC PRESSURED STEAM SETTING OF DYE ON WIEllB IN A TUBE Original Filed June 19, 1964 8 Shoots-Sheet 2 JACOB SE/PB/N I I I a f, 3' A ATTORNEYS.

Oct. 26, 1971 J. SERBIN 3,614,798

SUPERATMOSPHBRIC PRESSURED STEAM SETTING OF DYE ON WEB IN A TUBE Original Filed June 19, 1964 8 Sheets-Sheet 5 //VV/VTOR 4 JACOB SEER/N ATTORNEYS.

Oct. 26, 1971 5ERB|N 3,614,198

SUPERATMOSPHERIC PRESSURED STEAM SETTING OF DYE ON WEB IN A TUBE Original Filed June 19, 1964 8 Sheets-Sheet 4 lNVE/VTOR JA C05 SERE/A/ Wiwm ATTORNEYS.

J. SERBIN Oct. 26, 1971 SUPERATMOSPHERIC PRESSURE!) STEAM SETTING OF DYE 0N WEB IN A TUBE 8 Shoots-Sheet 5 Original Filed June 19, 1964 INVENTOR JACOB SE/i'Bl/V @ME-M- 16'? OR/Vf V5.

J. SERBIN 3,614,798

HAM SETTING OF DYE 0N WEB IN A TUBI".

Oct. 26, 1971 SUPERATMOSPHERIC PRESSURE!) ST 8 Sheets-Shem (5 Original Flled June 19, 1964 lNl/E/VTO/P JACOB SERB/A/ ATTORNEYS.

Oct. 26, 1971 J SERBlN 31,614,798

SUPERATMOSPHERIC PRESSURED STEAM SETTING OF DYE ON WEB IN A TUBE Original Filed June 19, 1964 8 Sheets-$heet '7 FIG. /0

l 0 1 82mm 0 350- 7.

' 2'82 0 .III 9 O a im 5. 2; m

3 W22, 7 W W ATTORNEYS.

3,614,798 Patented Oct. 26, 1971 3,614,798 SUPERATMOSPHERIC PRESSURE!) STEAM SETTING OF DYE ON WEB IN A TUBE .Iacob Serbin, Cedarbrook Hill Apt, Wyncote, Pa. 19095 Original application June 19, 1964, Ser. No. 380,740. Divided and this application May 28, 1968, Ser.

US. Cl. 8166 Int. Cl. D06p /00 13 Claims ABSTRACCT OF THE DISCLOSURE A method of setting dye on a dyed web of fabric comprising passing the web under tension through an atmosphere of live steam at superatmospheric pressure until said dye is set.

sequently be made into automotive and airplane seat belts.

This seat belt fabric is normally a narrow web of synthetic fibers, such as nylon fibers or Dacron polyester fibers. One of the major problems of the synthetic fibers, either in the dyeing of the seat belt webs or any other fabric made from the fibers, is that the fibers will not absorb dyes. Therefore any dyeing must take place at the surface of the fibers. A new field of dyeing is now being developed for the production of dyes which will react with the surface of synthetic fibers to give a permanent coloring. These dyes are generally referred to as reactive dyes. These dyes are discussed in detail in the article beginning on page 80 of the December 1962 issue of Textile World Magazine.

The normal method of using the reactive or the other synthetic fiber dyes in the past has been to first pad dye the fabric, dry it, and then set the dye either with saturated steam or by baking at a high temperature. Both of the dye setting procedures of the prior art had their disadvantages. The setting with live saturated steam at atmospheric pressure was a long process and the setting was not always as complete as desired. The setting with dry heat many times stopped the dyeing process and again the amount of setting was not as great as that desired.

Using the method of this invention, the dye setting speed is greatly increased. Additionally, the dye is fixed on the fiber to a far greater extent than that obtainable with the prior art methods.

It is therefore an object of this invention to provide a novel mehod for setting dye.

This and other objects of this invention are accomplished by providing a method of setting dye on a dyed web of fabric comprising passing the web, while under tension, through an atmosphere of live steam at superatmospheric pressure until said dye is set.

Other objects and many of the attendant advantages of this invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in combination with the accompanying drawings wherein:

FIG. 1 is a side elevational view of a dye setting machine usable in the method of this invention;

FIG. 2 is a schematic diagram of the process of dyeing using the machine of this invention;

FIG. 3 is an enlarged sectional view taken along the line 33 of FIG. 1;

FIGS. 4 and 4A comprise a sectional view taken along the line 4- of FIG. 3;

FIG. 5 is an enlarged sectional view taken along the line 5-5 of FIG. 4A;

FIG. 6 is an enlarged sectional view taken along the line 6-6 of FIG. 1;

FIG. 7 is a perspective view of one of the pressure seals of the machine of this invention;

FIG. 8 is a perspective view of one of the plates of the pressure seal shown in FIG. 7;

FIG. 9 is a sectional view taken along the line 9-9 of FIG. 7;

FIG. 10 is an enlarged sectional view taken along the line 1010 of FIG. 9;

FIG. 11 is a perspective view of a modified form of the pressure seal of the machine of this invention;

FIG. 12. is a perspective view of one of the plates of the pressure seal of FIG. 11;

FIG. 13 is a sectional view taken along the line 1313 of FIG. 11;

FIG. 14 is a perspective view taken along the line 1414 of FIG. 13;

FIG. 15 is a top plan view of a bank of pressure seals of this invention shown in association with an air equalization chamber; and

FIG. 16 is a top plan view of a portion of the electric resistance heaters used in the machine of this invention.

Referring now in greater detail to the various figures of the drawings where similar reference characters refer to similar parts, a dye setting machine usable for carrying out the process of the present invention is generally shown at 20 in FIG. 1.

The dye setting machine 20 is used in a process for dyeing continuous webs of fabric 22. The process is shown schematically in FIG. 2 and includes pad dyeing 24, dye setting 20, washing and rinsing 26, drying 28, cooling 30, resin padding 32, a two-step resin cure 34, and resin co0ling 36.

By way of specific example, continuous web of fabric 22 can be five parallel narrow webs, as shown in FIG. 2. As previously pointed out, the method of this invention finds particular utility with the dyeing of webs of fabric which will subsequently be made into automotive and aircraft seat belts. In the process of this invention the webs are held under high tension. For example, when using a 2 /2 inch width web, the tension throughout the process varies from 400 to 500 pounds per square inch. The tension is obtained by using driven draw rollers at the Various stations throughout the process. In this way the tension can easily be kept constant or varied at each step of the process. By carrying the process out under tension, the web is prevented from shrinking during the process. Additionally, the elongation of the final web is kept at a minimum. Thus, webbing produced according to the process of this invention will have a maximum of 18% elongation at a 2,500 pound pull.

With the exception of the dye setting machine, the other machines used for carrying out the process of this invention are well known in the dyeing art. The pad dyeing process 24 can either be exhaust or recirculating. As will be explained hereinafter, the dye setting machine can be used for saturated steam setting, superheated steam setting, or dry heat setting, depending on the particular dye being used. The wash and rinse step 26 removes any excess dye remaining on webs 22 after the dye has been set. The drying process 28 comprises two steps. Thus an air blast is first usd to remove any excess liquid, and circulated hot air completely dries the webs. The cooling of the dried webs is carried out by passing them over cooling cans which are conventional in the art.

If desired, the dyed webs can be given a resin coating. This is optional with the particular web being used. The resin coating serves the functions of protection for the web, such as for the purpose of resisting abrasion, and to give more body to the material. Any of the well known resins used for this purpose, such as acrylic resins, can be used. The resin is cured in a two-step process 34. The first step comprises a hot air blast and the second step comprises hot air circulation. The resin is then cooled on conventional cooling rolls.

As best seen in FIGS. 1, 4 and 4A, dye setting machine basically comprises a housing 38, an inlet door 40, an outlet door 42 and steam chambers 44 and 46 adjacent the inlet and outlet doors, respectively. The housing 38 is supported by four vertical beams 48 which are spaced by horizontal beams 50.

Referring now to FIG. 4A it is seen that chamber 46 has an outer vertical wall 52 which is part of housing 38 and an inner vertical wall formed by plate 54. As seen in FIG. 4A and FIG. 5, housing 38 has all the walls thereof thermally insulated with insulation material 56. Any conventional insulation material, such as fiber glass mats, can be used.

Door 42 is hinged to vertical wall 52 of housing 38 and covers opening 58 in the wall. Door 42 is also thermally insulated as shown at 60. The door is held closed by pi-votable latches 62 having fingers 64 adapted to engage flanges 66 of vertical wall 52. The door is additionally locked closed by turnscrews 68 which are conventional in the art. The purpose of doors 40 and 42 is to gain access to the interior of the machine for threading webs 22 therethrough.

As seen in FIGS. 3 and 4A, vertical plate 54 is provided with a plurality of horizontally and vertically aligned holes through which tubes 70 project. These tubes are welded in place, thereby sealing chamber 46 from the central interior chamber 72 of housing 38. Outside of the openings for tubes 70 there are no other openings connecting chamber 46 with interior chamber 72.

Four vertically aligned rollers 74 are mounted in chamber 46. As seen in FIG. 3, these rollers are mounted on shafts 76 which are in turn rotatably mounted in bearings 78-. Bearings 78 are mounted on beams 48 by bolts 80. As seen in FIG. 3, each bearing comprises a gasket 82, a first ring 84 which houses a sealing ring 86, a spacer ring 88, and a third ring which houses outer race 92, balls 94 and inner race 96. Although the specific bearing assembly 78 is used for the shafts 76, any other bearing assembly known to the art can be substituted.

A horizontal pipe 98 extends across the bottom of chamber 46. Pipe 98 is mounted in beam 48 by a conventional collar and coupling 100. As best seen in FIG. 3 the top of pipe 98 is provided with a plurality of spaced openings 102. The purpose of pipe 98 is to introduce steam under pressure into chamber 46. As seen in FIG. 3, a pipe 104 mounted in top 106 of housing 38 is in communication with the interior of chamber 46. A safety valve 108 is mounted on pipe 104. Thus, when the pressure of the steam in chamber 46- should exceed a predetermined maximum, safety valve 108- will automatically open, thereby lowering the pressure within the chamber.

As seen in FIGS. 4 and 4A, tubes 70 extend throughout the entire length of central chamber 72 of housing 38. Thus, these tubes are closed throughout the central portion and each has one end in communication with chamber 46 and the other end in communication with chamber 44. For a purpose to be described hereinafter, tubes 70 are inclined downwardly in going from chamber 44 to chamber 46.

Chamber 44 is similar in structure to chamber 46. Thus chamber 44 includes an outer vertical wall and an inner vertical wall defined by plate 112. Tubes 70 pass through holes in plate 112 that are aligned both vertically and horizontally. Each of the tubes 70 is welded to vertrical plate 112, thereby sealing the plate from the central portion 72 of the housing. Inlet door 40 seals opening 114 in wall and includes latches 116 and turnscrews 118. A steam inlet pipe 120 which is similar to pipe 98 projects across the entire bottom of chamber 44. Pipe 120 is provided With a plurality of openings 122 (one shown) for delivering the steam across the entire width of the chamber. As seen in FIG. 1, chamber 44 is also provided with a pipe 124 having a safety valve 126. Chamber 44 is also provided with four vertically aligned rollers 128. These rollers are substantially identical to rollers 74 in chamber 46 and have shafts which are journalled in vertical beams 48.

As seen in FIG. 4, Webs 22 enter chamber 44 by passing through seal assembly 130. This seal assembly will be described in greater detail hereinafter. Its purpose is to permit the entry of webs 22 into chamber 44 which at the same time effectively sealing the chamber in order to maintain a superatmospheric pressure therein.

As seen in FIG. 3 five aligned webs 22 enter the machine and pass therethrough simultaneously. Referring again to FIG. 4, after passing through the second uppermost tubes 70, webs 22 pass around uppermost roller 128 in chamber 44. In a similar manner, webs 22 pass back and forth from chamber 44 to chamber 46 by passing through tubes 70 and around rollers 128 and 74. Eventually, webs 22 pass through lowermost tubes 70 into the chamber 46 and out through seal assembly 132 which is identical in structure to seal assembly 130. Seal assembly 132 is mounted in vertical wall 52 of chamber 46.

In the embodiment shown, rollers 128 and 74 are merely idler rollers. However, if desired, these rollers can be driven to vary the tension within the dye setting machine in order to have it differ from the tension throughout the remainder of the process. As seen in FIG. 3, the alignment of webs 22 is maintained by vertical rods 134 which are positioned in front of tubes 70. The tops of rods 134 are mounted in horizontal bar 136 and the bottoms of rods 134 are mounted in horizontal bar 138. Horizontal bar 136 is in turn mounted on angle brackets 140 which are bolted to beams 48 and horizontal bar 138 is mounted on angle brackets 142 which are also bolted to beams 48. As seen in FIG. 3, all of the rods 134 are parallel and are arranged in pairs. Each pair is spaced apart a distance slightly greater than the width of a single web 22. Similar vertical rods 144 are supported by bars 146 and 148 in chamber 44. Thus, in passing through the machine, each web 22 will pass between a pair of rods 134 (FIG. 3) and a similar pair of rods 144. In this way, the alignment of the webs is maintained.

As seen in FIGS. 4, 4A and 5, a pair of parallel horizontal braces 150 extend along the entire bottom 152 of central portion 72 of housing 38. As seen in FIG. 5, each brace 150 is U-shaped and has the bridging section 154 uppermost. Mounted on braces 150 are a plurality of aligned pairs of U-shaped brackets 156. The bridging sections of brackets 156 are lowermost and are secured to the bridging section 154 of braces 150. A pair of electric resistance heater bars 158 is bolted to each pair of brackets 156. As seen in FIG. 5, heater bars 158 extend across substantially the entire width of housing 38. The heater bars .158 are electrically insulated from the remainder of the machine. This can be accomplished by either physically insulating the bars from brackets 156 or, in the embodiment shown, the brackets 156 can be made of a non-conducting material, such as ceramic.

A plurality of electric fans 160 is mounted in the lower portion of central portion 72. As seen in FIG. 5, these fans are driven by electric motors 162 which are mounted on side 164 of housing 38. This mounting is accomplished through brackets 166 which are bolted and welded to side 164 and support motors 162. The motor shafts 168 pass through openings 170 in the side 164.

A concave bafiie 172 extends from brace: 150 farthest from fans 160 to side .174 of housing 38. A horizontal bafile plate 176 extends along the entire length of central section 72. The ends of plate 176 are bent downwardly to form flanges 178 (FIG. 4) and 180 (FIG. 4A). As seen in FIGS. 4 and 4A, flanges 178 and 180 are welded to vertical plates 112 and 54, respectively, thereby sup porting bafile plate 176. As seen in FIG. 5, baffle plate 176 is spaced inwardly from walls 174 and 164. As further seen in FIG. 5, the edge 182 of baffle plate 176 which is adjacent wall 174 is convex upwardly. Edge 184 of baffle plate 176 which is adjacent wall 164 is concave upwardly.

Bafi'le plate 176 is positioned below all of the tubes 70 and is parallel thereto. In use, when fans 160 are operating, they will circulate air in the direction of arrows 186. Thus, as seen in FIG. air will be impelled from fans 160 across heaters 158 toward wall 174. The air is then turned upwardly with the help of baflie plate 172 and convex edge 182. This forces the air to circulate around tubes 70. The path of the air is then back to fans 160 across concave edge .184. The fans will not cause any substantial increase in pressure within the chamber formed in central portion 72, snice any excess air can escape through openings 170 around motor shafts 168.

In use, webs 22 which were just previously dyed in pad dyer 24 are fed into dye setting machine 20. When the webs are used for making seat belts, they are usually woven from synthetic fibers which have great tensile strength. Thus, polyester fibers, such as Dacron, or nylon fibers are most generally used. The most common of the synthetic fiber dyes must be set by saturated steam. In the prior art this steam was fed into chambers maintained at atmospheric pressure. Extensive time was required for the setting of the dye. Using the machine of this invention, saturated steam can be used at superatmospheric pressure. Thus a steam pressure of up to fourteen pounds per square inch gage can be maintained in the machine of this invention. Under normal operating conditions it has been found that saturated steam pressures of 1.3 pounds per square inch gage to 2.3 pounds per square inch gage give excellent results. These pressures give steam temperatures of from 216 F. to 219 F., respectively.

One of the critical features of most of the synthetic fiber dyes is that they must be set with saturated steam. Thus, if wet steam were used, the condensation of moisture on the interior of the setting machine housing and subsequent dripping of this moisture onto the dyed web will result in water spots. The use of superheated steam, although it would set the dye faster, also has disadvantages because it would likewise dry the dye, thereby giving an imperfect appearance of the dyed product. The use of saturated steam under pressure permits effective setting of the dye while at the same time obtaining a shorter setting time. This is because higher temperatures are obtained without the accompanying drying of the dye which would occur when using superheated steam.

The steam that is used in the machine of this invention is fed through pipe 98 into chamber 46. Suitable pressure and temperature controls are provided for the steam. Thus the pressure control is shown schematically at 188 in FIG. 1 and the temperature of the steam is recorded at 190 in FIG. 1. Any of the controls well known in the art, such as Foxboro controls, may be used. The steam, which is admitted under predetermined pressure, will then rise in chamber 46 and pass into tubes 70. Since the tubes are inclined upwardly and since the hot steam will rise, the steam will pass upwardly through the tubes toward chamber 44. However, in order to equalize the pressure in chamber 44, steam is also fed into this chamber through pipe 120. The steam entering chamber 44 is at the same pressure as that entering chamber 46. Therefore, once equilibrium has been reached the pressure throughout machine can be maintained constant. The temperature of the steam can be determined from meter 190.

Once equilibrium has been reached, the walls of tubes 70 should be at substantially the same temperature as the temperature of the incoming steam. This is because the walls are metallic and will readily conduct the heat from the steam. However, in order to insure that the Walls of the tubes are maintained at the same temperature as the steam, metallic electric resistance heaters 158 are provided. When these heaters are turned on, fans 160 will circulate the heat produced thereby into the air and around tubes 70. As previously pointed out there is no steam in central portion 72 of housing 38. Thus steam is present solely in chamber 44, chamber 46, and in tubes 70. Only air can pass around the tubes. Therefore, by circulating the heated air around tubes 70, the temperature of the tubes can be maintained at the same temperature as the steam. In this way, condensation of the steam on the interior walls of the tubes is prevented since there is no cold surface on which the steam can condense. Since condensation is substantially prevented, there is no fear of water marks forming on the dyed webs.

As seen in FIG. 6, the temperature within tubes is determined by thermometer bulb 192. This bulb rests within a sealed tube 194 which has one end opening into one of the tubes 70. Thermometer bulb 192 is connected through lead 196 to Fenwal temperature control 198. A safety valve 200 is mounted on tube 194. Safety valve 200 is an additional protection and will open if the pressure should become too great within tubes 70.

A second thermometer bulb 2012 is secured on the exterior of a tube 70 which is adjacent to the tube in which thermometer bulb 192 is in communication. Lead 204 is connected to bulb 202 and passes through wall 174 of housing 38. Lead 204 is also connected to Fenwal temperature control 206.

In use, temperature controls 198 and 206 determine the temperature of the steam within tubes 70 and the temperature of the walls of tubes 70. In this connection, it has been found that the temperatures of the steam and the Walls of the tube are relatively constant throughout the machine. Thus, the readings of these temperatures are determinative of the temperatures throughout the machine. When it is found that the temperature of the walls of the tubes is substantially less than the temperature of the steam within the tubes, the electric resistance heaters will be turned on and the walls of the tubes are heated until they are brought up to the same temperature as the steam. However, as pointed out above, for low steam pressures it has been found that the walls of the tubes are heated sufficiently by the steam itself to obviate the necessity of using the auxiliary electric heaters. The insulation of housing 38 prevents the tubes 70 from cooling down.

Even with the precautions mentioned above, it is still found that in some instances the steam will condense on the walls of the tubes. In such instances, the condensed moisture will roll down the walls of the tubes to the base of the tubes. In view of the fact that the tubes are inclined, the condensed moisture will then move toward the lower ends of the tubes which exit in chamber 46. The moisture is then conveniently removed from chamber 46 by inclined troughs 208 which are secured to each horizontal row of tubes (see FIGS. 3 and 4A). The moisture which is collected in the troughs will then flow into vertical collecting tubes 210 which are mounted on the sides of chamber 46. This is best seen with respect to lowermost tube 208 in FIG. 3. The water collected in tubes 210 is then de osited on inclined floor 212 of chamber 46. From there the water will pass into pipe 214. Pipe 214 is in turn connected to a conventional steam trap. In this way, none of the steam pressure within chamber 46 is lost through pipe 214.

Although not shown, troughs similar to troughs 208 can be used on the ends of tubes 70 in chamber 44. Under most circumstances the condensed moisture will move downwardly through the tubes into chamber 46. However, if any turbulance should occur in the steam, the moisture can be forced out of the upper ends of the tubes 70. For this reason the troughs may also be used in chamber 44.

Condensed moisture within the chamber will pass through pipe 216 which also has a steam trap thereon.

The use of the tubes in combination with the troughs 208 has been found to be particularly advantageous in the setting of the dye. Thus if any condensation should result, the moisture will roll down the sides of the tubes and be collected in the bottoms of the tubes. There is little danger of the condensed moisture dripping on the dyed webs, thereby getting water marks. Likewise when there is a moisture buildup within the tubes, the moisture will flow to the ends of the tubes and be collected in troughs 208 where it is safely carried to the sides of chamber 46. Thus, it is again seen, there is no fear of the condensed water dripping on the dyed webs. These double safety features have been found to be extremely effective. In the prior art, where the dye was set at atmospheric pressure with saturated steam, it was found that steam would condense on the top of the setting chamber and would eventually drip off onto the dyed fabric, thereby getting water marks. This problem is substantially completely obviated by the machine of this invention.

As seen in FIG. 16 a portion of the electric resistance heaters 158 used in this invention is shown schematically. For the purpose of illustration, heaters 158 have been specifically numbered as 218, 220, 222, 223, 226, 228, 230, 232, 234, 236, 238, 240, 242, 244, 246 and 248, respectively. Thus sixteen heaters have been shown as being exemplary of the Wiring arrangement for the heaters. Lead lines 250, 252, 254, 256, 258 and 260 supply the current for two-thirds of the heaters used. Lead lines 262, 264 and 266 supply the current for one-third of the heaters used. By way of example, it is seen that when current is passed through lines 252 and 254, heaters 222, 224, 228 and 230, among others, will be energized. Likewise, when current is passed through lines 262 and 264, heaters 226 and 232, among others, will be energized. By a similar analysis it is seen that out of every six heaters, four of them will be energized by upper leads 250, 252, 254, 256, 258 or 260 and two of them will be energized by leads 262, 2-64 or 266. In this way, two-thirds of the heaters and one-third of the heaters can be independently controlled. Thus, when only a small amount of auxiliary heat is needed, current will be passed solely through leads 262, 264 and 266. When a slightly greater amount of heat is needed, current will be passed solely through leads 250, 252, 254, 256, 258 and 260. When an extremely large amount of heat is needed, current will be passed through all of the leads. Since the heaters energized by any set of leads are staggered according to a regular pattern, the heat within central chamber 72 will be substantially uniform. Although only sixteen heaters have been shown as being exemplary, obviously the number of heaters can be increased or decreased depending upon the size and requirements of the machine. For the machine shown, a total of sixty-six bar heaters has been found to be most effective.

Seal assembly 130 is shown in FIG. 15. This seal assembly comprises a pressure chamber 268 and a plurality of individual seals 270. Seals 270 are arranged in aligned pairs with one of each pair being bolted to lateral wall 272 of chamber 268 and the other being bolted to lateral wall 274 of chamber 268. Additionally, it is seen that the seal bolted to wall 272 projects into chamber 268 and the seal bolted to wall 274 extends outwardly of the wall. Chamber 268 is sealed and substantially pressure tight. As seen in FIGS. 4 and 4A, a pipe 276 is tapped into the base of the chamber. The purpose of the pipe 276 is to permit the introduction of air under pressure within chamber 268. In this way the pressure within the chamber 268 can be made to equal the pressure within chambers 44 and 46. Thus, there will be no pressure drop caused by a pressure differential between chambers 44 and 46 and the pressure within chamber 268 of seal assemblies 130 and 132. In this way, leakage of steam out of the machine caused by a drop in pressure is substantially eliminated.

A first embodiment of a seal 270 which is utilizable in seal assembly or 132 is shown in FIG. 7. Seal 270 includes a rear chamber 278 which tapers inwardly as it approaches the front of the seal. A rectangular plate 280 is secured to the rear edge of chamber 278. This securement is obtained by flanges 282 which are welded to the walls of chamber 278. Plate 280 is provided with a plurality of holes 284. Bolts are passed through holes 284 in order to secure the seals to chamber 268. Bottom wall 286 (FIG. 9) is provided with upturned flanges 288 (FIG. 7) which are welded to the side walls 290 of chamber 278. Bottom wall 286 additionally includes a substantially horizontal forward extension 292. Forward extension 292 is also provided with upturned flanges 294 (FIG. 7). The forward edge of extension 292 is bent perpendicularly downward to form flange 296.

A horizontal plate 298 projects forwardly of extension 292 and is secured thereto by U-shaped lip 300 which engages flange 296. The forward portion of plate 298 is bent downwardly, then upwardly to form a U-shaped socket 302. A substantially flat plastic sheet 304 is mounted on top of plates 292 and 298. Sheet 304 is secured in place by bolts 306 which pass through the sheet and its supporting plates. The bolt holes in the sheet are countersunk in order to recess the bolt heads. In this way, the sheet provides a substantially smooth surface. The forward portion 308 of sheet 304 is bent downwardly and is received in U-shaped socket 302.

Top wall 310 of chamber 278 includes a horizontal extension 312. Extension 312 includes a pair of downwardly projecting side flanges 314 (FIG. 10). Flanges 294 of bottom wall 292 abut flanges 314 and are welded thereto. Extension 312 also includes upwardly projecting vertical flange 316 at the forward edge thereof. A plastic plate 318 is secured to forward extension 312 by countersunk bolts 320. The forward portion 322 of plate 318 is curved upwardly. Curved plate 324 having a forward U-shaped lip 326 is secured to the top of plastic plate 318 by countersunk bolts 328. The forward portion 322 of plate 318 is received in lip 326. The rear of plate 324 is bent vertically upward to form flange 330.

A pair of laterally spaced parallel plastic blocks 332 is mounted on plastic plate 304. This securement is partially obtained by bolts 334 (FIG. 9) which pass through plate 298, plate 304, and into the bottom of blocks 332. As seen in FIG. 9, blocks 332 rest on plate 304 throughout its entire length. Referring now to FIG. 8 it is seen that plate 318 includes a central portion 336 having a T-extension 338 at its rear. As best seen in FIG. 10, blocks 332 are laterally spaced a distance which is slightly greater than the width of central portion 336 of plate 318. Thus, as seen in FIG. 9, central portion 336 is received between the blocks 332. As further seen in FIG. 9, the T-extension 338 of plate 318 rests on the top of blocks 332. If desired, the tops of blocks 332 can be recessed to receive the T-extension.

A pair of substantially vertical supports 340 are secured on the sides of blocks 332. Each plate includes an inwardly projecting flange 342 at the bottom thereof (FIG. 10). A bolt 344 passes through each block 332, plate 304, plate 298, and flange 342. Bolts 344 are secured in place by associated nuts 346. The tops of supports 340 are inwardly offset, as best seen in FIG. 10 and are provided with a pair of aligned holes. A shaft 348 having externally threaded ends passes through these holes. The shaft is secured in place by nuts 350 secured on the threaded ends. A pair of coiled compression springs 352 is telescoped over shaft 348. Each of these springs includes a rearwardly extending finger 354 having a hooked end which engages vertical flange 316 of horizontal section 312. Each spring 352 also includes a forwardly extending finger 356 which has a hooked end which engages vertical flange 330 of plate 324.

In use, webs of fabric are fed through a pair of aligned seals 270. The webs can be fed through either end of the seals. Thus, as best seen in FIG. 9, by providing the flared curved surfaces of plates 304 and 318, the web can easily be fed into the forward end of the seal. This is accomplished by merely lifting plate 318 relative to fixed plate 304. After the web has been fed, the plate 318 is automatically returned to the position shown in FIG. 9, by the pressure of finger 356 of spring 352. Thus, it is seen that spring 52 will maintain a continual pressure against the plate 318. In this way, seal 270 will be maintained in a normally closed condition. Air leakage through the sides of the seal is prevented by the abutting relation of the sides of plate 318 with plastic blocks 332, as best seen in FIG.

If desired, the web can also be fed through the rear side of seals 270. To facilitate the entry of the web, the portions of plates 318 and 304 which are located between blocks 334 are provided with rear bevelled edges 358 and 360, respectively. In order to facilitate the insertion of the web 22 from either end of the seal, a long narrow strip of rigid sheet metal can be bent in half and the leading edge of the web 22 placed within the bent metal. The rigid bent metal can then be forced through a pair of aligned seals. Once the metal has been pulled through the seals, it is removed and the web can then be continued along its path in the machine or throughout the remainder of the process. Generally, one width of material will be continually used in the machine. For a Width of 2 /8 inches, the normal width of a seat belt web, blocks 332 will be spaced a distance slightly greater than 2 /8 inches. Thus the possibility of leakage is substantially lessened since there are no openings in the seal other than the opening needed to accomodate the web being passed therethrough. When using widths that are substantially smaller or greater than 2 /8 inches, seals of different sizes can be used.

Plates 304 and 318 and blocks 332 are made of a heat resistant plastic having a low coeflicient of friction. Additionally, the plastic must be sufficiently flexible to permit it to yield under the pressure of spring 352. A plastic which has been found to be particularly useful for this invention is Teflon (polytetrafiuoroethylene). This plastic is desirable because of its high heat resistance, extremely low coeflicient of friction, and the fact that it is almost completely chemically inert. Another plastic which may be used under some applications is nylon.

A modified embodiment of a seal which may be used with this invention is generally shown at 362 in FIG. 11. Seal 362 is similar to seal 270 in that it includes a rear chamber 362 having a mounting plate 366 on the rear thereof. As seen in FIG. 13, top wall 368 of chamber 364 includes a forward horizontal extension 370. Mounted on extension 370 is a rectangular plastic plate 372. A rectangular metal plate 374 is mounted on top of plastic plate 372.

The lower wall 276 of chamber 364 includes a forward horizontal extension 378. Mounted against extension 378 is the T-extension 380 (FIG. 12) of lower plastic plate 382. As further seen in FIG. 12, plastic plate 382 includes a forward rectangular section 384. A pair of spaced parallel metallic blocks 386 is mounted against the bottom of plastic plate 372. The rear undersurfaces of blocks 386 are recessed to receive the outer extremities of T-extension 380, as best seen in FIG. 11. As is also apparent from FIG. 11, the sides of horizontal extensions 370 and 378 of chamber 364 terminate inwardly of blocks 386. A rectangular metallic plate 388 which is approximately equal in size and shape to T-extension 380 of plastic plate 382 is mounted under and against the T-extension. Two pairs of aligned bolts 390 pass through aligned holes in plate 374, plate 372, blocks 386, T-extension 380 and plate 388. These bolts are secured in place by nuts 392 (FIG. 13). As previously pointed out, extensions 370 and 378 are spaced inwardly of blocks 386, and therefore bolts 390 will not pass through the extensions.

As best seen in FIG. 14, blocks 386 are spaced a distance which is slightly greater than the width of horizontal portion 384 of plate 382. As seen in FIG. 13, horizontal extension 384 is movable relative to plate 372. In this manner, rectangular portion 384 performs the same sealing function as the forward portion 336 of plate 318 of seal 270. Coiled compression springs 394 hold rectangular portion 384 of plate 382 resiliently in place. Thus it is seen that a cylindrical rod 396 is positioned below plate 382. Rod 396 is provided with outer recesses 398 (FIG. 14) which receive blocks 386. Thus, the upper surface of rod 396 can force plate 382 into close abutment with plate 372 without interference from blocks 386, as seen in FIG. 14.

Shafts 400 are threadedly secured in cylinder 396 and pass through aligned openings in blocks 386, plate 372 and plate 374. Springs 394 are telescoped over these shafts. Nuts 402 are threadely received on the tops of shafts 400. It is thus seen that the tension on springs 394 can be increased or decreased by the appropriate rotation of nuts 402 on shafts 400. Since the shafts 400 are fixedly secured to cylinder 396 and are freely slidable in blocks 3'86, plate 372 and plate 374, the increasing of the tension on springs 394 will in turn increase the pressure of plate 382 against plate 372. In this way an effective seal can be maintained, and the pressure on the seal can be varied depending upon the thickness of the web passing through the seal. If desired, a second pair of nuts can be added to shafts 400 above nuts 402. These second nuts can serve as lock nuts in order to insure that the tension on springs 394 will not inadvertently be varied once it is set.

Bolts 404 pass through aligned holes in plate 374, plate 372, blocks 386 and crossbar 406 in order to give additional stability to the seal. Bolts 404 are secured in place by associated nuts 408. Additionally, bolts 410 pass through aligned holes in plates 374 and 372 and are threadedly received in blocks 386 to further stabilize the seal.

Seal 362 is used in substantially the same manner as seal 270. The only opening into the interior of the seal is through the resiliently mounted plate 382. The threading of the web within the seal is carried out in the same manner as the threading of seal 270. However, when it is desired to thread the web through the front of the seal, it is necessary to first lower the tension on springs 394. This is accomplished by rotating nuts 402 upwardly at shafts 400. This facilitates forcing the front of plate 382 downward, thereby providing for the easy insertion of the Web through the front of the seal. Once the web has been inserted, the tension on the springs is again increased to the desired degree in order to insure free slidability of the web while at the same time insuring an effective seal against steam leakage and a resultant loss in pressure.

In seal 362, plates 372 and 382 are made of a heat resistant plastic with a low coeificient of friction. Again, T elflon is a preferred material. All of the metallic parts of seals 270 and 362 are preferably made of stainless steel in view of the fact that the seals will be continually contacted by steam. Thus, stainless steel is preferred because of its rust resistance.

In FIGS. 4 and 4A it is seen that the individual seals of each seal assembly face inwardly with respect to their respective chambers 44 and 46. The reason for this is that it has been found that this arrangement provides a more efficient pressure seal. Thus there is no buildup of steam pressure within chambers 278, which would occur if the steam were in direct contact with the chambers. As previously pointed out, when desired, air under pressure can be fed into chamber 268 of each seal assembly in order to obtain an equal pressure between chambers 44 and 46 and the interiors of the seal assemblies. When the dye setting machine is used at low pressures, complete seal assemblies and 132 may not be necessary. Thus, instead of having pairs of spaced seals mounted on a pressure chamber, single seals mounted on a plate may be used. In this way, the web 22 will pass through 1 1 only one seal, instead of two, in entering machine 20 and pass through only one seal on leaving machine 20.

Either seal 270 or seal 362 may be used on the machine of this invention. Each of these seals enjoys its own specific advantages. With respect to seal 270, it can be seen that the web can easily be inserted from either end of the seal. Thus, all that is necessary is to lift upper plate 318 against the pressure of spring 352 in order to insert the web through either end. Additionally, the flared fronts of the plates in seal 270 aid in the sliding of the Web inwardly from the front of the seal.

The main advantage of seal 362 is that the spring tension is adjustable by adjusting nuts 402. Thus, if it is found that there is a great deal of resistance to the sliding of the web over the plastic plates, the spring tension can be lessened. Likewise, if it is found that there is a great deal of leakage around the web, the spring tension can be increased.

It can be seen by reference to the aforementioned December 1962 issue of Textile World Magazine that there are numerous reactive dyes presently in use for the dyeing of synthetic fibers and materials woven from these fibers. In fact, the dyeing art is expanding every day. Even with the present knowledge of synthetic fiber dyes, it has been found that these dyes can be set under Varying conditions, depending on the exact nature of the dye. Thus, although the majority of dyes are now set with saturated steam there are other dyes that can be set with superheated steam and still others which can be set with intensive dry heat. The machine of this invention is adapted for use with any one of these dyes. Thus, as explained above, the machine of this invention can be used -by supplying saturated steam under pressure for setting the dyes. If desired, after saturated steam is supplied under pressure, the steam can be superheated by the use of the electrical resistance heaters. Thus by heating the air around tubes 70 to a higher temperature than the temperature of the steam being fed under pressure, the steam can be superheated. In some instances, the dye can be set merely by the use of dry heat. Here again, the dyed webs will be fed through tubes 70. However, no steam will be admitted to the tubes. Instead, all of the heat will be generated by the electric resistance heaters and heated air will be circulated around tubes 70, thereby heating the tubes. This in turn will cause the heating of the air within the tubes and the subsequent setting of the dye on the webs.

The speed of travel of the dyed webs through the machine of this invention will normally range from 5 to 35 yards per minute, with an average speed of yards per minute. The actual speed used for any given run will generally depend on the color of the dye being used. Thus, for light colors, a faster speed will be used and for dark colors, a slower speed will be used.

Without further elaboration, the foregoing will so fully illustrate my invention, that others may, by applying current or future knowledge, adopt the same for use under various conditions of service.

What is claimed as the invention is:

1. A method of setting a dye on an onset dye impregnated web of fabric comprising applying a tension to said web, passing said web while under tension through tubing closely surrounding but spaced from said web, said tubing being open at its ends but being otherwise imperforate and passing steam at superatmospheric pressure through said tubing to set said dye, the imper-forate walls of said tubing having a length which is substantially as long as needed to set said dye while dye is under said steam.

2. The method of claim 1 wherein said web passes through a plurality of tubes, and the exteriors of said tubes are heated in order to minimize the condensation of the steam on the interior of said tubes.

3. The method of claim 1 wherein said fabric is formed from synthetic fibers.

4. The method of claim 3 wherein said synthetic fibers comprise nylon.

5. The method of claim 3 wherein said synthetic fibers comprise a polyester.

6. The method of claim 3 wherein said dye is a reactive dye.

7. The method of claim 1 wherein said steam is at a pressure of between 1.3 pounds per square inch gage and 2.3 pounds per square inch gage.

8. The method of claim 1 wherein said steam is at a temperature of between 216 'F. and 219 F.

9. The method of claim 1 wherein said web is under a tension of between 400 pounds per square inch and 500 pounds per square inch, said tension being applied by draw rollers.

10. The method of claim 1 wherein said steam is saturated.

11. The method of claim 1 wherein said web follows a tortuous path through a plurality of tubes.

12. The method of claim 11 wherein said tubes are substantially horizontally extending and are vertically spaced.

13. The method of claim 1 wherein said tension is suflicient to prevent said web from shrinking during said dye setting.

References Cited UNITED STATES PATENTS 1,738,946 12/1929 Chapin et al. 8-149.3 2,460,206 l/l949 Wenty 8l49.3 3,097,910 7/1963 Andrew et al. 8-54.2 2,199,233 4/ 1940 Williams 8-151 OTHER REFERENCES Schlaeppi, American Dyestuif Reporter, pp. 377-383, June 2, 1958.

Kern, American Dyestuff Reporter, pp. 366-373, May 15, 1961.

The Textile Manufacturer, October 1949, pp. 488-490.

DONALD LEVY, Primary Examiner U.S. Cl. X.R. 

